The deal was that they get the B767's with subsidies if they go ahead with the B787 purchase. So they are looking at a complete failure of there star class if they did cancel because they couldnt keep up 33" without those subsidies.
So unless they were 100% silly and didnt care about customers or profit they they wouldnt cancel any orders, and by then the B767's will be verging on 20 years old so they will need a replacement anyway.